/Engine/Plugins/Experimental/LandscapePatch/Source/LandscapePatch/Public/LandscapePatchManager.h
These get called by the landscape system to apply the patches to the height/weight maps.
virtual void Initialize_Native ( const FTransform & InLandscapeTransform, const FIntPoint & InLandscapeSize, const FIntPoint & InLandscapeRenderTargetSize )